MC_Power

PLCopen motion icon

Function Block - Requests to either enable the drive and close the loop, or disable the drive and open the loop.

Inputs

Input	Data Type	Range	Unit	Default	Description
Enable	BOOL	FALSE, TRUE	N/A	No default	When this transitions goes to high: The control closes the servo loop. Sends a command to the drive to enable. When this transitions go to low: The control opens the servo loop. Sends a command to the drive to disable.
Axis	AXIS_REF	1 to 256	N/A	No default	Name of a declared instance of the AXIS_REF library function. See Axis Name and Number. See AXIS_REF Structure.
EnablePositive	BOOL	FALSE, TRUE	N/A	No default	For future enhancement.
EnableNegative	BOOL	FALSE, TRUE	N/A	No default	For future enhancement.
BufferMode	SINT	0 (zero)	N/A	No default	Unused.

Outputs

Output	Data Type	Range	Unit	Description
Status	BOOL	FALSE, TRUE	N/A	Indicates the enabled/disabled state of the drive.
Busy	BOOL	FALSE, TRUE	N/A	Always FALSE.
Error	BOOL	FALSE, TRUE	N/A	Indicates an invalid input was specified.
ErrorID	INT	-32768 to +32767		Indicates the error if Error output is TRUE. See PLCopen Function Block ErrorIDs.

Remarks

This function or function block returns cached data.
See Program a Multi-Core Controller.

See Function Blocks - General Rules about how inputs and outputs work.
The Status output indicates the state of the position loop.
- If the position loop is open, the axis command position is set to the actual position of the axis and tracks the actual position.

Be careful if there is more than one instance of MC_Power FB for the same drive, scanned in the same cycle.
The problem arises when one instance requests the drive to enable and the other requests the same drive to disable.
To avoid this trap, it is recommended to have only one instance of MC_Power for all active programs.

Figure 1: MC_Power

FBD Language Example

Not available.

FFLD Language Example

IL Language Example

Not available.

ST Language Example

(* MC_Power ST example *)
Inst_MC_Power( CloseLoopReq, Axis1, TRUE, TRUE, 0 );
//Inst_MC_Power is an instance of MC_Power function block
DriveIsOn := Inst_MC_Power.Status;     //store the Status output into a user defined variable